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oot/tools/ZAPD/lib/libgfxd/README.md
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17 KiB

Installing

Run make for a single-threaded build, or make MT=y for a multi-threaded build. Copy libgfxd.a to your lib directory, and gfxd.h to your include directory.

Example usage

Example source code:

#include <stdio.h>
#include <gfxd.h>

static int macro_fn(void)
{
	/* Print a tab before each macro, and a comma and newline after each
	   macro */
	gfxd_puts("\t");
	gfxd_macro_dflt(); /* Execute the default macro handler */
	gfxd_puts(",\n");

	return 0;
}

int main()
{
	/* Read from stdin and write to stdout */
	gfxd_input_fd(fileno(stdin));
	gfxd_output_fd(fileno(stdout));

	/* Override the default macro handler to make the output prettier */
	gfxd_macro_fn(macro_fn);

	/* Select F3DEX as the target microcode */
	gfxd_target(gfxd_f3dex);

	/* Set the input endianness to big endian, and the word size to 4 */
	gfxd_endian(gfxd_endian_big, 4);

	/* Print an opening brace */
	gfxd_puts("{\n");

	/* Execute until the end of input, or until encountering an invalid
	   command */
	gfxd_execute();

	/* Print a closing brace */
	gfxd_puts("}\n");
}

Example input (binary):

0xe7000000, 0x00000000,
0xfc127e03, 0xfffffdf8,
0xb900031d, 0xc8112078,
0xb6000000, 0x000e0000,
0xb7000000, 0x00012000,
0xfa000000, 0xffffffff,
0x040030bf, 0x000002e0,
0xb1000204, 0x00020604,
0xb1080a0c, 0x000a0e0c,
0xb10a1012, 0x000a120e,
0xb1140200, 0x00140016,
0xb8000000, 0x00000000,

Example output:

{
	gsDPPipeSync(),
	gsDPSetCombineLERP(TEXEL0, 0, SHADE, 0, 0, 0, 0, 1, COMBINED, 0, PRIMITIVE, 0, 0, 0, 0, COMBINED),
	gsDPSetRenderMode(G_RM_FOG_SHADE_A, G_RM_AA_ZB_OPA_SURF2),
	gsSPClearGeometryMode(G_LIGHTING | G_TEXTURE_GEN | G_TEXTURE_GEN_LINEAR),
	gsSPSetGeometryMode(G_CULL_BACK | G_FOG),
	gsDPSetPrimColor(0, 0, 0xFF, 0xFF, 0xFF, 0xFF),
	gsSPVertex(0x000002E0, 12, 0),
	gsSP2Triangles(0, 1, 2, 0, 1, 3, 2, 0),
	gsSP2Triangles(4, 5, 6, 0, 5, 7, 6, 0),
	gsSP1Quadrangle(5, 8, 9, 7, 0),
	gsSP1Quadrangle(10, 1, 0, 11, 0),
	gsSPEndDisplayList(),
}

Input/output methods

The input consists of any number of Gfx packets, and the output is the decompiled macros in plain-text. The endianness and microcode type of the input can be set using gfxd_endian and gfxd_target.

Several methods of doing I/O are available. No method is selected by default, meaning there will be no input, and any output will be discarded.


void gfxd_input_buffer(const void *buf, int size)
void gfxd_output_buffer(char *buf, int size)

Use the buffer pointed to by buf, of size bytes.


void gfxd_input_fd(int fd)
void gfxd_output_fd(int fd)

Use read() / write() with the provided file descriptor, fd.


typedef int gfxd_input_fn_t(void *buf, int count)
typedef int gfxd_output_fn_t(const char *buf, int count)
void gfxd_input_callback(gfxd_input_fn_t *fn)
void gfxd_output_callback(gfxd_output_fn_t *fn)

Use the provided callback function, fn. fn should copy at most count bytes to/from buf, and return the number of bytes actually copied. The input callback should return 0 to signal end of input.

Handlers

The macro handler function is responsible for writing the output of each decompiled macro. The default macro handler is gfxd_macro_dflt, but this can be changed with gfxd_macro_fn. The new handler can extend the default function by calling gfxd_macro_dflt within it, or it can override it completely.


int gfxd_macro_dflt()

The default macro handler. Outputs the macro name, dynamic display list pointer if one has been specified, and then each argument in order using the function registered using gfxd_arg_fn (gfxd_arg_dflt by default), and returns zero. Because it is designed to be extended, it only outputs the macro text, without any whitespace or punctuation before or after. When this function is used as the sole macro handler, it will output the entire display list on one line without any separation between macros, which is probably not what you want.


void gfxd_macro_fn(gfxd_macro_fn_t *fn)

Set fn to be the macro handler function. fn can be null, in which case the handler is reset to the default.


void gfxd_arg_dflt(int arg_num)

The default argument handler for gfxd_macro_dflt. For the argument with index arg_num, calls gfxd_arg_callbacks, and prints the argument value if the callback returns zero, or if there is no callback for the given argument.


void gfxd_arg_fn(gfxd_arg_fn_t *fn)

Set fn to be the argument handler function, called by gfxd_macro_dflt, for each argument in the current macro, not counting the dynamic display list pointer if one has been specified. fn can be null, in which case the handler is reset to the default. This only affects the output of gfxd_macro_dflt, and has no observable effect if gfxd_macro_dflt is overridden (not extended).

Argument callbacks

Callbacks can be registered that will be executed when an argument of a certain type is encountered. The default argument handler gfxd_arg_dflt will execute callbacks as needed using gfxd_arg_callbacks. If a callback returns non-zero, gfxd_arg_dflt will not output anything. This is to allow callbacks to override the default argument output. Otherwise, gfxd_arg_dflt will output the argument value after the callback function's output.


int gfxd_arg_callbacks(int arg_num)

Examines the argument with index arg_num and executes the callback function for that argument type, if such a callback is supported and has been registered. This function returns the value that was returned by the callback function. If no callback function has been registered for the argument type, zero is returned.

Most argument callbacks have some extra parameters containing information that might be relevant to the argument that triggered the callback. The extra information is extracted only from the current macro, as gfxd does not retain any context information from previous or subsequent macros. If any of the extra parameter values is not available in the current macro, the value for that parameter is substituted with -1 for signed parameters, and zero for unsigned parameters.


typedef int gfxd_tlut_fn_t(uint32_t tlut, int32_t idx, int32_t count)
void gfxd_tlut_callback(gfxd_tlut_fn_t *fn)

Set the callback function for palette arguments. The argument type is gfxd_Tlut. The palette index is in idx and the number of colors in count.


typedef int gfxd_timg_fn_t(uint32_t timg, int32_t fmt, int32_t siz, int32_t width, int32_t height, int32_t pal)
void gfxd_timg_callback(gfxd_timg_fn_t *fn)

Set the callback function for texture arguments. The argument type is gfxd_Timg. The image format is in fmt and siz, the dimensions in width and height, and the palette index in pal.


typedef int gfxd_cimg_fn_t(uint32_t cimg, int32_t fmt, int32_t siz, int32_t width)
void gfxd_cimg_callback(gfxd_cimg_fn_t *fn)

Set the callback function for frame buffer arguments. The argument type is gfxd_Cimg. The image format is in fmt and siz, and the horizontal resolution in width.


typedef int gfxd_zimg_fn_t(uint32_t zimg)
void gfxd_zimg_callback(gfxd_zimg_fn_t *fn)

Set the callback function for depth buffer arguments. The argument type is gfxd_Zimg.


typedef int gfxd_dl_fn_t(uint32_t dl)
void gfxd_dl_callback(gfxd_dl_fn_t *fn)

Set the callback function for display list arguments. The argument type is gfxd_Dl.


typedef int gfxd_mtx_fn_t(uint32_t mtx)
void gfxd_mtx_callback(gfxd_mtx_fn_t *fn)

Set the callback function for matrix arguments. The argument type is gfxd_Mtxptr.


typedef int gfxd_lookat_fn_t(uint32_t lookat, int32_t count)
void gfxd_lookat_callback(gfxd_lookat_fn_t *fn)

Set the callback function for lookat array arguments. The argument type is gfxd_Lookatptr. The number of lookat structures (1 or 2) is in count.


typedef int gfxd_light_fn_t(uint32_t light, int32_t count)
void gfxd_light_callback(gfxd_light_fn_t *fn)

Set the callback function for light array arguments. The argument type is gfxd_Lightptr. The number of light structures is in count.


typedef int gfxd_seg_fn_t(uint32_t seg, int32_t num)
void gfxd_seg_callback(gfxd_seg_fn_t *fn)

Set the callback function for segment base arguments. The argument type is gfxd_Segptr. The segment number is in num.


typedef int gfxd_vtx_fn_t(uint32_t vtx, int32_t num)
void gfxd_vtx_callback(gfxd_vtx_fn_t *fn)

Set the callback function for vertex array arguments. The argument type is gfxd_Vtxptr. The number of vertex structures is in num.


typedef int gfxd_vp_fn_t(uint32_t vp)
void gfxd_vp_callback(gfxd_vp_fn_t *fn)

Set the callback function for viewport arguments. The argument type is gfxd_Vp.


typedef int gfxd_uctext_fn_t(uint32_t text, uint32_t size)
void gfxd_uctext_callback(gfxd_uctext_fn_t *fn)

Set the callback function for microcode text arguments. The argument type is gfxd_Uctext. The size of the text segment is in size.


typedef int gfxd_ucdata_fn_t(uint32_t data, uint32_t size)
void gfxd_ucdata_callback(gfxd_ucdata_fn_t *fn)

Set the callback function for microcode data arguments. The argument type is gfxd_Ucdata. The size of the data segment is in size.


typedef int gfxd_dram_fn_t(uint32_t dram, uint32_t size)
void gfxd_dram_callback(gfxd_dram_fn_t *fn)

Set the callback function for generic pointer arguments. The argument type is gfxd_Dram. The size of the data is in size.

General settings

These functions control general input and output settings.


void gfxd_target(gfxd_ucode_t ucode)

Select ucode as the target microcode. ucode can be gfxd_f3d, gfxd_f3db, gfxd_f3dex, gfxd_f3dexb, or gfxd_f3dex2. The microcode must be selected before gfxd_execute, as no microcode is selected by default.


void gfxd_endian(int endian, int wordsize)

Select endian as the endianness of the input, and wordsize as the size of each word in number of bytes. endian can be gfxd_endian_big, gfxd_endian_little, or gfxd_endian_host (the endianness of the host machine). wordsize can be 1, 2, 4, or 8. Big endian is selected by default, with a word size of 4.


void gfxd_dynamic(const char *arg)

Enable or disable the use of dynamic g macros instead of static gs macros, and select the dynamic display list pointer argument to be used. arg will be used by gfxd_macro_dflt as the first argument to dynamic macros. If arg is null, dynamic macros are disabled, and gs macros are used. Also affects the result of gfxd_macro_name, as it will return either the dynamic or static version of the macro name as selected by this setting.


void gfxd_enable(int cap)
void gfxd_disable(int cap)

Enable or disable the feature specified by cap. Can be one of the following;

  • gfxd_stop_on_invalid: Stop execution when encountering an invalid macro. Enabled by default.
  • gfxd_stop_on_end: Stop execution when encountering a SPBranchList or SPEndDisplayList. Enabled by default.
  • gfxd_emit_dec_color: Print color components as decimal instead of hexadecimal. Disabled by default.
  • gfxd_emit_q_macro: Print fixed-point conversion q macros for fixed-point values. Disabled by default.
  • gfxd_emit_ext_macro: Emit non-standard macros. Some commands are valid (though possibly meaningless), but have no macros associated with them, such as a standalone G_RDPHALF_1. When this feature is enabled, such a command will produce a non-standard gsDPHalf1 macro instead of a raw hexadecimal command. Also enables some non-standard multi-packet texture loading macros. Disabled by default.

void gfxd_udata_set(void *ptr)
void *gfxd_udata_get(void)

Set or get a generic pointer that can be used to pass user-defined data in and out of callback functions.

Execution

Decompilation is started using the gfxd_execute function. When gfxd is executing (i.e. after gfxd_execute has been entered, and before it returns), the general settings and the I/O settings should not be changed.


int gfxd_execute()

Start executing gfxd with the current settings. For each macro, the macro handler registered with gfxd_macro_fn is called. Execution ends when the input ends, the macro handler returns non-zero, when an invalid macro is encountered and gfxd_stop_on_invalid is enabled, or when SPBranchList or SPEndDisplayList is encountered and gfxd_stop_on_end is enabled. If execution ends due to an invalid macro, -1 is returned. If execution ends because the macro handler returns non-zero, the return value from the macro handler is returned. Otherwise zero is returned.

Macro information

The following functions can be used to obtain information about the current macro and its arguments. They should only be used in custom handlers and callbacks from within gfxd_execute. If used elsewhere, their behavior is undefined.


int gfxd_macro_offset()

Returns the offset in the input data of the current macro. The offset starts at zero when gfxd_execute is called.


int gfxd_macro_packets()

Returns the number of Gfx packets within the current macro.


const void *gfxd_macro_data()

Returns a pointer to the input data for the current macro. The data is not byte-swapped. The data has a length of sizeof(Gfx) * gfxd_macro_packets().


int gfxd_macro_id()

Returns a number that uniquely identifies the current macro. The number will be one of the constants in gfxd.h.


const char *gfxd_macro_name()

Returns the name of the current macro. If the macro does not have a name (i.e. it's invalid), null is returned. If a dynamic display list pointer has been specified, the dynamic g version is returned. Otherwise the static gs version is returned. The returned pointer is invalidated by a subsequent call to gfxd_macro_name.


int gfxd_arg_count()

Returns the number of arguments to the current macro, not including a dynamic display list pointer if one has been specified.


int gfxd_arg_type(int arg_num)

Returns a number that identifies the type of the argument with index arg_num. The number will be one of the constants in gfxd.h.


const char *gfxd_arg_name(int arg_num)

Returns the name of the argument with index arg_num. Argument names are not canonical, nor are they needed for macro disassembly, but they can be useful for informational and diagnostic purposes.


int gfxd_arg_fmt(int arg_num)

Returns the data format of the argument with index arg_num. The return value will be gfxd_argfmt_i for int32_t, gfxd_argfmt_u for uint32_t, or gfxd_argfmt_f for float. When accessing the value of the argument with gfxd_arg_value, the member with the corresponding type should be used.


const gfxd_value_t *gfxd_arg_value(int arg_num)

Returns a pointer to the value of the argument with index arg_num. The value is a union of type gfxd_value_t with the following layout;

typedef union
{
	int32_t		i;
	uint32_t	u;
	float		f;
} gfxd_value_t

const gfxd_value_t *gfxd_value_by_type(int type, int idx)

Returns a pointer to the value of the argument that is of type, and has order idx in all arguments of that type. An idx of zero returns the first argument that has the specified type. If there is no argument with the given type and order, null is returned.


int gfxd_arg_valid(int arg_num)

Returns non-zero if the argument with index arg_num is "valid", for some definition of valid. An invalid argument generally means that the disassembler found inconsistencies in the input data, or that the data can not be reproduced by the current macro type. The argument still has a value that can be printed, though the value is not guaranteed to make any sense.

Custom output

When the default handlers are overridden or extended, the custom handler functions will want to do some output of their own. The following methods are available for inserting custom text into the gfxd output.


int gfxd_write(const void *buf, int count)

Insert count bytes from the buffer at buf into the output. The number of characters written is returned.


int gfxd_puts(const char *str)

Insert the null-terminated string at str into the output. The number of characters written is returned.


int gfxd_printf(const char *fmt, ...)

Insert the printf-formatted string described by fmt and additional arguments into the output. Limited to 255 characters. The number of characters written is returned.


int gfxd_print_value(int type, const gfxd_value_t *value)

Insert the type-formatted value into the output. The type should be one of the constants in gfxd.h. The number of characters written is returned. The macro argument with index n can be printed with gfxd_print_value(gfxd_arg_type(n), gfxd_arg_value(n)).